Hygrometer



L. S; ULLMAN.

Weather indicator.

Patented Sept. 13, 1859.

Nor 25,457.

W W M M N. Pnzns. Phula-Lithagnphur, Washington. ac

FFIQE.

LOUIS S. ULLMAN, OF NASHVILLE, TENNESSEE.

HYGROMETER.

Specification of Letters Patent No. 25,457, dated September 13, 1859.

To all whom it may concern:

Be it known that I, LOUIS S. ULLMAN, of Nashville, in the county ofDavidson and State of Tennessee, have invented a new and ImprovedHygrometer, which I term the Oriental and Occidental WVeather-Indicator;and I do hereby declare that the following is a full, clear, and exactdescription of the same, reference being had to the accompanyingdrawings, forming part of this specification, in which-- Figure 1 is afront view. Fig. 2 is a central section. Fig. 3 is a view of the capsuleand tail-like appendage of the Arabian plant known as chahajin or chahanconstituting the principal portion of the instrument, and represented inthe natural condition.

Similar letters of reference indicate corresponding parts in the severalfigures.

Certain plants, as the chahajin or chahan of Arabia represented in theaccompanying drawing, and the Geranium eroclium well known in thiscountry and in Europe, have attached to their capsules a tail-likeappendage, part of which is naturally of a spiral form, and tends tounwind itself, or wind itself up as the atmosphere in which it isexposed becomes more or less moist.

My invention consists in the construction of a hygrometer of convenientform by combining an index, or its equivalent, and a graduated dial orscale in any manner, substantially as hereinafter described, with thecapsule and spiral tail-like appendage of the above specified plants.

The drawing represents the most convenient form of my improvedhygrometer and after describing that form a few remarks will suflice toexplain the other form that may be adopted.

A, is a box which may be of brass, or other metal, wood or othersubstance, made with a solid back a, but with a movable glazed front B,around the interior of which is an open dial plate or ring I), graduatedin any suitable or convenient manner. This box must have one or moresuitable openings 7', in the sides or other part for the admission ofair.

0 (Z 6, is the sensitive portion of the hygrometer; 0, being thecapsule; (Z, the spiral portion of its tail-like appendage, and e,

i the extreme portion of the said appendage which is not twisted. Theportion 6, is firmly secured by wax or cement or by any other means tothe back a, of the box, in such a manner that the capsule, and thespiral portion project forward in the center of the box perpendicularlyto the sides and front thereof.

7, is the index having a hole in its center which fits tightly on thecapsule o.

g, is a small collet secured to a frame upon the glass it, of the frontof the box to receive the front extremity of the capsule and prevent itslateral displacement. This collet is large enough for the capsule towork freely within it.

2', is a plate secured to the interior of the back of the box for thepurpose of covering up the portion 6, and giving a finished appearanceto the interior of the instrument.

As the spiral portion (Z, of the plant winds up, or unwinds itself withthe changes in the hygrometric condition of the atmosphere the capsule0, having the index attached is caused to turn back and forth, and ifthe dial is properly graduated the index will indicate the degree ofmoisture in the atmosphere, and so foretell changes of weather. Thedial, besides being graduated, or instead of being graduated, may bemarked in any manner that will be best understood for the purpose ofindicating the changes of weather.

Instead of attaching an index to the capsule to indicate upon a dial orcircular scale, a small weight may be suspended from a thread which isattached to, and wound around the capsule, and the said weight having avertical scale arranged near it will ascend and descend the said scaleas its suspending thread is wound up or unwound by the action of thespiral portion cl, upon the capsule c. The suspended weight may workwithin a glass tube having a properly graduated scale placed at the backof it. The suspended weight is an equivalent for the index f, and thevertical scale the equivalent for the dial or circular scale 6.

I do not claim the combination of an index with a vegetable substancetwisted by art. Neither do I claim the use of the naturally spiralportions of plants when not applied, as I have described, in combinationWith dials and indices or their equivalents. index and dial, or theirequivalents, substan- But tially as herein described to constitute aWhat I claim as my invention, and desire hygrometer.

to secure by Letters Patent, is LOUIS S. ULLMAN.

The combination of the capsule and Witnesses:

naturally spiral tail-like appendage of W. H. BURY,

either of the plants herein specified With an R. A. CAMPBELL.

